The Perfect Linux Firewall Part I -- IPCop
This document describes how to install the GNU/Linux GPL IPCop firewall and create a small home office network. In the second installment we cover creating a DMZ for hosting your own web server or mail server and the Copfilter proxy for filtering web and email traffic.
This is intended Read More →

The
Open Systems Interconnection (OSI) model
is primarily used today as a teaching tool. It conceptually divides computer network architecnto seven layers in a logical progression. The lower layers deal with electrical signals, chunks of binary data, and routing of these data across networks. Higher levels cover network requests and responses, representation of data, and network protocols Read More →

TCP keepalive
In order to understand what TCP keepalive (which we will just call keepalive) does, you need do nothing more than read the name: keep TCP alive. This means that you will be able to check your connected socket (also known as TCP sockets), and determine whether the connection is still up and running or Read More →